The major causes responsible for the reduction in Biodiversity

The components of biodiversity are so interdependent that any change in the system leads to a major imbalance and threatens the normal ecological cycle. The major causes responsible for the reduction in Biodiversity are as under:

Habitat Loss

The primary cause of the loss of biodiversity is not direct human exploitation but the habit destruction that inevitably results from the various anthropogenic activities.

Explosion of Human Population

(i) Among these anthropogenic activities, the first problem arises with the explosion of human population. Being the second most populous country in the world, India faces severe strains on her ecosystems due to vast human population.

Population pressure creates the need for more and more land for agricultural purposes, haphazard growth of urban centres, mass migration of people and animals, deforestation and degradation of forest cover, pollution, and depletion of natural resources and so on. The requirements of land are usually fulfilled through the wrong implementation or exploitation of cultural lands of rural areas or through the destruction of forests.

(ii) Human Encroachment:

More than half of the forestlands in India have been badly affected by human encroachment and development. The ethnic as well as rural people living in the vicinity of forest areas tend to encroach forest stretches; thus causing a loss of tree cover.

(iii) Unchecked Industrialisation:

On the other hand unchecked industrialization, coupled with construction of roads, canals, river valley projects, mining or quarrying activities threaten to disrupt the delicate ecological balance and in most of the cases the pressure is concentrated over the rural and undisturbed parts of our country.

(iv) Shifting Cultivation:

Various hilly areas, shifting cultivation is a common practice to certain tribal groups and villagers. This shifting cultivation is very much responsible for the degradation of local flora and faunal content. It also decreases the soil fertility and increases the rate of soil erosion.

(v) Indiscriminate use of groundwater:

In plains the problem is somewhat different. Here the ever increasing agricultural needs require more and more water for irrigation, resulting in the indiscriminate use of groundwater. It causes a rapid downfall in the water level as well as a perturbation in the normal hydrological cycle.

(vi) Pollution:

The prime man made defilement of nature is pollution, which has virtually eaten away our natural resources.

(vii) Introduction of exotic species: Introduction of exotic species that threaten native flora and fauna directly by predation or by competition and also indirectly by altering the natural habitat. Most of the threatened species are land based, with more than half occurring in forest. Fresh water and marine habitats especially coral reefs are also very vulnerable.